In a statement, officials explained the rationale for the move (via UFC.com):

“UFC has informed Germaine de Randamie and her management team that she is being removed as the women’s featherweight champion due to her unwillingness to fight the No. 1 ranked contender, Cris ‘Cyborg’ Justino. Subsequently, top contender Justino will face newly signed Invicta FC featherweight champion Megan Anderson for the UFC women’s featherweight title in the co-main event of UFC 214; Cormier vs. Jones 2, July 29 in Anaheim, Calif.

“UFC maintains that any champion is expected to accept fights against the top contenders in their respective weight classes in order to maintain the integrity of the sport.”